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This is a guide for beginners having trouble with the game.

1. What class to choose?

Melee = Higher chance to take damage and be cornered by mob but deals high dps(damage per second).

Recommended: Viking- Has good dps and has an upgradeable ground slam that clears mobs and early bosses like a charm.

Ranged = Much weaker than melee (lower dps) but gives more protection to beginners

Recommended: Necromancer- okay dps and can summon up to three skeletons that do melee damage and block the mob.

Not Recommended: Pirate- shoots projectiles alternately out of both guns making it difficult to accurately hit anything.

2. Okay, I'm here. Now what?

There are six waves in an arena, the sixth is always a boss. The arena changes after the sixth wave. After thirty waves a new level will open up.

These are items you will find in the arena:

Traps: Can be used to kill mobs and bosses, as they follow you into a trap.
Boxes: have gold and silver/crystal keys.
Chests: Brown chests will open at approach, Golden ones require silver keys. Both usually have gold. Blue ones give crystal and require crystal keys to open.
Shrubs: Can be hit to get gold, sometimes also hide monsters.
Potions: Give temporary stat boosts or fill up health. Some can also decrease health/stats or spawn enemies, so be careful.
Statues: Pray to the Holy statue to get stat boosts that last until you die. The Devil statue gives better buffs than the holy one but has a 50% chance to give debuffs, so your call.

3. Explore

Now, as soon as you drop in the arena, start exploring. At each wave, new items and chests drop in the arena, so make sure you collect those. Sometimes these may appear before a wave:

Treasure Fort: Buy stat boosts and items with the collected gold. Needs silver key to open. When you get out of this, the arena layout will have changed, so start exploring again.
Crypt: Avoid if low level character
Dungeon: same as crypt.

If you can't kill mobs easily, try luring them into traps.

Also, each wave is triggered after the last enemy in the present wave is killed. If you want to explore to your heart's content, it might be a good idea to leave one enemy alive.

Going into your skills screen pauses the game, but the game is not paused when you are in the 'charm' selection screen. Any active skill you upgrade will first have to be assigned before it can be used. Look at the HUD at the bottom centre of your screen.

Also, you will get certain powerful active/passive relics that will help you. These are generally found on killing bosses, or can be bought in shops(Treasure Forts).

Dying on normal difficulty will take away all your relics and items and gold, but you will retain your level, skills and the crystals you obtained.

If you have any questions or clarifications, comment on this and I will modify the guide accordingly.

Edit 1: Okay, I just completed the game on Normal with the Viking. A hundred something waves. There are some problems with boss scaling in the game. There were times where I faced really low hp bosses in advanced levels and times when I faced really tough bosses in starting levels. This needs to be fixed.

The final advice I can give is this- crypts and dungeons offer relics at the end, but it's really not worth it. It is very easy to come across advanced enemies here, and the super-cramped space means an early death sentence. Also, many a time, you'll find a boss here. These bosses can be way high leveled(some can even one shot you) and the cramped space means that you're surely going to die. So avoid dungeons and crypts.

Also, sometimes the mandatory boss fight at the 6th wave is inside a 'boss dungeon'. In such cases, you'll have a thin corridor that will end up in and a medium sized room where the boss will spawn. DO NOT back into this corridor after the boss spawns. He'll corner you and kill you, as there's no space to dodge his attacks, and he'll be blocking the corridor exit.